教方法
假如有表Comp
表如
CompID UserIF
A B
A C
B F
在要求把CompID中有和UserID字段有系的合充回表里, 比如A有和F合.
后的
CompID UserID
A B
A C
A F
B B
B C
B F
教SQL怎么?




[解决办法]
select a.CompID,b.UserIF from (select distinct compid from comp) a,(select distinct userif from comp) b order by a.compid